Try to find the following books:
-- American folklore : an encyclopedia (1996)
-- Archetypes and motifs in folklore and literature (2005)
-- Encyclopedia of urban legends (2012)
-- The Greenwood encyclopedia of world folklore and folklife (2006)
Question? Ask your librarian!
Do you use Wikipedia? Since anybody can edit the content of Wikipedia, the information may not include various viewpoints and some sources may not be up-to-date. Until you can critically evaluate the information, you may also use CREDO Reference. This is created by scholars and you can understand various perspectives and definitions.